Fixation of an intraocular implant to the iris

ABSTRACT

For attaching an intraocular implant having pincher like clamping arms forming a pinching area between end portions of the clamping arms to an iris of an eye, the implant is positioned against a surface of the iris in the anterior chamber of the eye, a passage in a distal end portion of an ophthalmologic surgical instrument in the anterior chamber of the eye is positioned against a surface portion of the iris closely adjacent the pinching area, and suction is applied to the passage and at least one of the end portions of the clamping arms is urged towards the iris, causing a tuck of iris material adhered to the passage to be inserted into the pinching area. Thus, a tuck adhering to the passage can easily be introduced into the pinching area between the clamping arms. An instrument and an implant specifically adapted for this method are described as well.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/055,416 filed Jan. 23, 2002.

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to a method and an instrument for inserting a tuckof iris tissue between clamping arms of an intraocular device to beattached to a surface of the iris in an anterior chamber of an eye. Theinvention also relates to an ophthalmologic implant to be attached bypinching a tuck of iris tissue.

In U.S. Pat. Nos. 4,215,440 and 5,192,319 intraocular lenses, aredescribed which are to be implanted in the anterior chamber of the humaneye by clamping a tuck of iris tissue between pincher-like armsprojecting from an optical portion of the lens.

Advantages of attaching an intraocular lens to a plea of iris tissue arethat the iris does not need to be perforated, that no parts of the lensproject through the iris, that the attachment can be made quickly andwith few manipulations, and that the attached lens is also securedagainst rotation about its optical axis. Forming a tuck of iris materialis carried out by stroking iris tissue into a tuck and by bringing thetuck between ends of pincher-like arms projecting from the opticalportion of the lens by, at the same time, pushing one of the clampingarms away from the iris relative to the other clamping arm so that theiris opens up. Although many eye surgeons routinely perform thistechnique, it requires special skill and training.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a solution whichfacilitates the formation of a tuck of iris tissue and the introductionof that tuck between the clamping arms of the implant.

According to the invention, this problem is solved by providing a methodfor attaching an intraocular implant having pincher-like clamping armsforming a pinching area between the clamping arms to an iris of an eye,including: positioning the implant against a surface of the iris in theanterior chamber; positioning a passage in a distal end portion of anophthalmologic surgical instrument in the anterior chamber against thesurface of the iris closely adjacent the pinching area; and applyingsuction to the passage and urging at least one of the end portions ofthe clamping arms towards the iris, causing a tuck of iris materialadhered to the passage to be inserted into the pinching area.

The invention further provides an ophthalmologic surgical instrument forinserting a tuck of iris tissue in a pinching area between clamping armsof an intraocular implant to be attached to a surface of the iris in ananterior chamber of an eye, including: an elongate distal end portionfor insertion into the anterior chamber, the distal end portiongenerally extending in an axial direction and comprising a laterallyfacing entry passage in a distal tip section of the distal end portion,the passage having an entry area bounded by a rim extending in a singleplane for sealingly contacting the iris tissue surface and a crestfacing away from and extending essentially parallel to the plane, forurging open the pinching area between the clamping arms, and a conduitextending from the passage for transferring a vacuum to the passage fromat least a more proximal portion of the instrument. Such an instrumentis specifically adapted for carrying out the method according to theinvention.

Since the iris material is adhered to the passage of which the rimessentially sealingly contacts the iris tissue surface, a tuck adheringto the passage can easily be introduced into the pinching area betweenthe clamping arms which are urged towards the iris by passing the crestof the distal end portion through pinching area between the clampingarms. The iris material follows the crest so that a tuck of the iristissue is inserted between the clamping arms.

The invention further provides an intraocular implant havingpincher-like clamping arms for engaging a tuck of iris tissue forattaching the implant to the surface of the iris in an anterior chamberof an eye, the pincher-like clamping arms projecting from a centralportion of the implant, and defining a pinching area in a positionspaced from the central portion, a gap being enclosed by the centralportion and the clamping arms, the central portion having a positioningspot for positioning a tip of an ophthalmologic instrument in a positionopposite across the gap of the pinching area between the clamping arms.Such an implant is specifically adapted for use in combination with anelaboration of the invention in which the clamping arms are urgedtowards the iris by the distal end portion of the instrument exerting aforce towards the iris on a central portion of the implant while thecrest thereof is passed through the pinching area between the clampingarms in a direction away from the implant. To facilitate keeping the tipof the distal end portion of the instrument exerting a force on theimplant in a position relative to the implant, and thereby facilitatecontrol over the position of the implant prior to its completeattachment to the iris, the implant is provided with a positioning spotfor positioning the tip of the ophthalmologic instrument. This spot isengaged by the tip of the ophthalmologic instrument and makes it lessprone to slipping over the surface of the implant.

Particular elaborations and embodiments of the invention are set forthin the dependent claims.

Further features, effects and details of the invention appear from thedetailed description and the drawings. In the brief description, theorientation of views refers to an orientation of the eye and surgicalinstruments where the anterior side of the eye is facing verticallyupwards.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially enlarged and cut-offside view in cross-section ofa first example of an ophthalmologic instrument according to theinvention, with a distal end portion of the instrument inserted in theanterior chamber of an eye,

FIG. 2 is an enlarged top plan view of an intraocular implant accordingto the invention engaged by a distal end portion of an instrumentaccording to the example shown in FIG. 1,

FIG. 3 is an enlarged cut-off view in cross-section along the lineIII-III in FIG. 1,

FIG. 4 is a view according to FIG. 3 showing a distal end portion of asecond example of an ophthalmologic instrument according to theinvention and shows end portions of clamping arms of an implant insuccessive stages,

FIG. 5 is a view according to FIG. 4 in which the end portions of theclamping arms have reached an end stage clamping a plea of iris tissue,

FIG. 6 is a side view in cross-section along the line VI-VI in FIG. 4

FIG. 7 is a cut-off side view of a distal end portion of a third exampleof an ophthalmologic instrument according to the invention,

FIG. 8 is a view in cross-section along the line VIII-VIII in FIG. 7,

FIG. 9 is a bottom view of the distal end portion shown in FIGS. 7 and8,

FIG. 10 is a side view in central cross-section across a distal endportion of a fourth example of an ophthalmologic instrument according tothe invention operating on iris tissue and clamping arms of an implant,

FIG. 11 is a top plan view of the situation according to FIG. 10,

FIG. 12 is a schematic representation of a fifth example of anophthalmologic instrument according to the invention,

FIG. 13 is a side view of a sixth example of an ophthalmologicinstrument according to the invention,

FIG. 14 is an enlarged top plan view of a portion of the instrumentaccording to FIG. 13,

FIG. 15 is a side view along the line XV-XV in FIG. 14,

FIG. 16 is an enlarged top plan view of a portion of a variant of aninstrument according to FIG. 13,

FIG. 17 is a side view along the line XVII-XVII in FIG. 14,

FIG. 18 is a top plan view of a distal end portion of a sixth example ofan ophthalmologic instrument according to the invention operating oniris tissue and clamping arms of an implant,

FIG. 19 is a side view of a tip section of the distal end portion shownin FIG. 18, and

FIG. 20 is a frontal end view of the tip section according to FIG. 19.

DETAILED DESCRIPTION

A first elaboration and embodiment of the invention is described withreference to FIGS. 1-3.

The main purpose of the present, proposed ophthalmologic surgicalinstrument is to insert a tuck of iris tissue 1 into a slit 2 betweenclamping arms 3 of an intraocular implant 4 to be attached to a surface5 of the iris 6 in an anterior chamber 7 of an eye. Preferably, theclamping arms normally abut in the pinching area and the clamping forcepreferably varies relatively little with the distance between thepinching surfaces of the clamping arms 3. In FIG. 1—in which a distalend portion of the instrument is shown in an enlarged representation—theinstrument is shown in operation in a situation in which the distal endportion 8 is inserted into the anterior chamber 7 of an eye 9 via anincision 10 in the cornea 11 of the eye. Preferably, such an incision ismade in a portion of the cornea most closely and most remote from avertical medial plane dividing the left and right half of the body.

The instrument has an elongate distal end portion 8 for insertion intothe anterior chamber 7 of the eye. In the present example, the needle 8generally extends in an axial direction and has a passage 12 in a distaltip section 13. The passage 12 has an entry facing laterally away fromthe central longitudinal axis of the needle in the area of the entry.The entry area is bounded by a rim 14 extending in a single plane 15 foressentially sealingly contacting the iris tissue surface 5 so that iristissue adheres to the rim 14 of the passage 12 in response to suctionapplied to that passage 12. Furthermore, the needle has a clamping armdisplacement crest 16 facing away from and extending essentiallyparallel to the plane 15. For inserting the tuck of iris material, thecrest 16 urges the arms 3 apart to open the slit 2 to allow passage ofthe tip end section 13 into and through the slit 2 followed by a tuck ofiris tissue 1 which is then released and left clamped in the slit 2.

For transferring a vacuum to the passage 12 from at least a moreproximal portion of the instrument 17, a lumen 18 extends axiallythrough the needle 8. The vacuum source communicating with the lumen 18includes an energy storage in the form of a spring 19, a structureformed by a piston 20 for generating suction in response to releasingenergy from the energy storage 19, and an operating structure in theform of a double lever 21 selectively pivotable from a position (asshown) retaining the piston 20 and a position in which the piston 20 isreleased, for releasing energy stored in the energy storage 19. Sincethe suction is generated in response to releasing stored potentialenergy, both operation and construction can be kept very simple. Becausevacuum supply from an external source in not necessary, a connection tosuch a source can be dispensed with. This in turn contributes to thetidiness during surgery and facilitates the accurate control over theinstrument.

The transfer of vacuum to the passage 12 can be damped, for instance byapplying the vacuum via a restriction. Adherence of the iris tissue tothe passage and formation of the tuck can thereby be carried outgradually, which facilitates control and improves adherences during theformation and insertion into the slit of the tuck of iris tissue.

The double lever is pivotally mounted to a housing 26 in which first asyringe 27 can be mounted via an open side 30. The operating flange 28of the syringe is then received in a slit 29 in the housing. Next, thespring 19 and the piston 20 can be inserted into the syringe 27 via apassage 31 in the proximal end of the housing 26. For engaging thepiston 20, the double lever has a recess 22 adapted for receiving anedge portion of an end plate 23 of the piston 20. The double lever ispivotable about an axis 24. A spring 25 urges the lever 21 into aposition in which an arm 32 of the lever 21 at a proximal side of axis24 is displaced towards the piston 20 for engaging the piston 20 and inwhich an operating arm 33 of the lever 21 extending along the housing 26is in its position projecting from the housing 26. Pressing theoperating arm 33 of the double lever 21 towards the housing 26 causesthe double lever 21 to release the piston 20. This can be carried outwith the hand that also holds the instrument.

Since the vacuum source includes an energy storage 19, a structure 20,27 for generating suction in response to releasing energy from theenergy storage 19 and an operating structure 21 for releasing energystored in the energy storage 19, the instrument can be provided in theform of a compact self-contained unit which does not need to beconnected to an external vacuum source.

This can moreover be realized in a simple construction since the suctiongenerating structure has a suction chamber 27 having an internal volumebounded by a wall including a movable wall portion 20, and the energystorage is provided in the form of an elastic member 19 for urging themovable wall portion 20 into a direction causing the volume of thesuction chamber to increase. Since the movable wall portion in the formof a piston 20 is axially movable in a channel, the conduitcommunicating with the channel across a closed end of the channel,allows the use of a conventional syringe, for instance a 1 ml syringe,as a disposable component of the proposed instrument.

The syringe also forms a control structure for displacing a limitedvolume (for instance at most less than 1 to 3 ml) of fluid duringapplication of the vacuum. An advantage of limiting the amount of fluiddisplaced during application of suction to the passage 12 is, that theremoval of undue amounts of liquid (which is usually gelled duringintraocular surgery) out of the eye in the event the rim 14 does notseal adequately against the iris surface 5 is avoided, even if aninitially strong vacuum is applied and the effective cross-sectionalsurface of the passage 12 is relatively large for effectively adheringiris tissue to the passage 12.

In use, attaching an implant 4 to the iris 6 using the instrumentaccording to the present example is a carried out as follows: first theimplant 4 is positioned against a surface 5 of the iris 6 in theanterior chamber 7 of the eye 9. Then, the passage 12 in the needle 8 ispositioned in the anterior chamber 7 of the eye 9 against a surfaceportion 5 of the iris 6 closely adjacent the slit 2 between end portionsof the clamping arms 3 to be attached to the iris 6. Then, suction isapplied via the passage 12 and at least one of the end portions of theclamping arms 3 is urged towards the iris 6, causing a tuck of irismaterial 1 adhered to the passage 12 to be inserted into the slit 2.Finally, the instrument releases the tuck of iris material by removingthe suction applied via the passage 12.

The crest 16 temporarily enlarges the slit 2 and succeeding portions ofthe needle 8 urging at least one of the clamping arms 3 away from theother clamping arm 3. This can for instance be carried out by pushingone end of one clamping arm 3 away from the other clamping arm 3 in ananterior direction with the crest 16 slightly off centre relative to theslit 2 so that it initially engages one clamping arm 3 only. Once theslit 2 is large enough, the tip end section of the needle 8 can be movedtowards the other arm (i.e. to and slightly beyond the centre of theslit 2) entraining the tuck of iris material 1 into the slit 2.

The movement of the crest 16 in anterior direction relative to theclamping arms 3 can also be achieved by moving the crest 16 centrallyinto the slit 2 so that both clamping arms 3 are bent away from eachother and the slit 2 is enlarged such that it accommodates to the needle8 passing through.

It is observed that, preferably, the tuck of iris material 1 adhered tothe passage 12 is not substantially displaced in anterior direction. Thedisplacement of the arms 3 relative to the tuck of iris material 1 ispreferably achieved by urging the arms 3 towards the iris 6 while thepart of the needle 8 where the passage 12 adheres to the tuck of irismaterial 1 is retained in position. Thus, the arm or arms 3 of theimplant are displaced in posterior direction while the needle 8 and thetuck of iris material 1 are held in an essentially stationary positionin the eye 9.

To facilitate control over movements of the clamping arms 3 and the tuckof iris tissue 1 and to reduce the need of inserting several instrumentsinto the eye 9 at the same time, the forces urging the end portion orend portions of the clamping arms 3 towards the iris 6 are preferablyexerted on the implant 4 by the distal end portion 8 of the surgicalinstrument.

According to the present example, the forces for the urging the endportions of the clamping arms 3 towards the iris 6 are exerted on theimplant 4 at a central portion 34 of the implant 4 in a position locatedon the side of the gap 36 opposite the side of the gap 36 where the slit2 between the clamping arms 3 is located. This allows to urge the crest16 into the slit 2 between the arms 3 and to urge the implant 4 towardsthe iris 6 with a single, slight tilting movement of the needle 8 duringwhich the tip end moves in posterior direction relative to the sectionurging the clamping arms 3 apart. In the area of the incision 10, theneedle 8 can in principle not move otherwise than axially, but therequired tilting movement is very small and the iris 6 and the implant 4can move slightly in posterior direction as the movement is made.Therefore, the required tilting movement of the needle 8 can be madewithout exerting undue stress on the cornea 11 in the area of theincision 10.

The implant shown in FIGS. 1-3 is specifically adapted for facilitatingthe technique according to this example of inserting a tuck of iristissue 1 into the slit 2 between the clamping arms 3. To facilitatekeeping the tip 38 of the needle 8 of the instrument exerting a force onthe implant 4 in a position relative to the implant 4, and to therebyfacilitate control over the position of the implant 4 prior to itscomplete attachment to the iris 6, the implant is provided with apositioning spot 37 for positioning the tip 38 of the ophthalmologicinstrument. This spot 37 is engaged by the tip 38 of the ophthalmologicinstrument and counteracts slipping of the tip 38 over the surface ofthe implant 4.

According to the present example, the positioning spot 37 is formed by arecess 37 adapted for receiving at least a portion of the tip 38 of theophthalmologic instrument. Compared with a positioning spot formed by aprojection, this is advantageous, because no complicated miniaturestructures need to be provided on the tip of the needle for receiving aprojection. The recess 37 is open towards the slit 2. However, therecess can also be surrounded by a wall surrounding the entire recess sothat a projection at the tip of the needle 8 can engage the recess toimprove control over the position of the implant 4 prior to attachmentto the iris 6 in every direction along the iris surface 5. Thepositioning spot can also be formed by a projection for engaging an eyein at least a portion of the tip of the ophthalmologic instrument.

To facilitate attaching the implant 4 to the iris 6 operating via anincision at the side of an eye facing the median longitudinal plane ofthe head, it is advantageous that the tip section 13 extends at an angleto a next, more proximal section 40. The tip section 13, which isintended to lie flat on the iris surface 5 with the rim 14 of the entryarea that extends in a plane parallel to the tip section 13, preferablyextends at an angle of up to 60.degree and preferably of 5-40.degreerelative to the more proximal section 40 of the needle 8.

The length of the tip section 13 distal from the angled or curvedportion of the needle is preferably at least 5 mm, so that the angled orcurved portion and the more proximal section 40 extending at an angle tothe tip section 13 remain outside the eye. This, in turn, isadvantageous for preventing inadvertent contact of the needle 8 to theinside of the cornea.

Since the rim 14 around the entry extends in a plane 15 essentiallyparallel to the tip section 13 of the needle 8, it can easily be broughtin sealing contact with the iris surface 5 by holding the needle 8 insuch an orientation, that the tip section 13 extends along the surface 5of the iris 6.

The tip end 37 of the needle 8 is closed and blunt, so that the risk ofcausing lesions on iris tissue 1 or the lens is reduced. By alsoproviding that the tip is rounded, the risk of lesions is furtherreduced.

To increase the effective cross-sectional surface of the passage 12while keeping the needle 8 slim, in particular in the section where thecrest 16 to be passed through the slit 2 is located, the passage 12 hasan elongate shape. An elongate shape of the passage 12 (length to widthratio preferably larger than 1:2 and more preferably at least 1:3 andpreferably at most 1:8) is also advantageous, because the tuck to whichthe passage is to adhere is inherently elongate. The elongate shape ofthe passage also allows a crest portion of the tuck to be retained inthe chamber behind the passage. The width of the passage 12 ispreferably at least half the width of the needle in the area of thepassage 12. To provide an effective sealing to the iris surface 5 whileallowing iris tissue to slide smoothly into the passage 12, the rim 14preferably has a rounded shape.

During the application of suction to the iris tissue 1, it isadvantageous if it can easily be seen whether the iris tissue 1 actuallyadheres to the passage 12 and, where applicable, is drawn into thepassage. To this end, at least the section of the needle 8 in the areaof the passage 12 is transparent. This allows to visually monitor theeffect of the applied suction and also provides feedback to the surgeonwith respect to the need of moving the passage 12 further in posteriordirection or of applying more suction. The transparent needle can forinstance be made of high strength glass such as for instance Schott'sDURAN, a borosilicate glass 3.3 (according to ISO 3585 and variousnational equivalents) or a suitable plastic material. It is alsopossible to improve visibility of the adherence of iris material byproviding that not the whole needle or a tip section of the needle istransparent, but by providing a transparent window opposite the passage.

For allowing easy passage through the slit 2 between the clamping arms 3of the implant and on the other hand providing a needle which issufficiently stiff and which provides sufficient room for the passageand the lumen in the needle 8, the width of the section including thecrest 16 is preferably less than 1 mm and more preferably between 0.2and 0.5 mm. The needle thickness can for instance be in a range from21-28 G and preferably 23-26 G. Moreover, the distal end portion ingeneral will typically be free from cutting tools or any other tools.

Furthermore, according to the elaboration shown in FIGS. 1-3, thepassage 12 against which the tuck of iris tissue 1 adheres is passedthrough the slit 2 (an alternative in which the passage does not passthrough the slit is discussed below with reference to in FIGS. 10 and11). An advantage of passing the area where the iris tissue 1 is heldagainst the needle 8 through the slit 2 is that the introduction of irismaterial 1 into the slit 2 supports the formation of the tuck of tissueto be engaged by the clamping arms 3 exactly in the position of the slit2.

In FIGS. 4-6, one of the above-described examples of the process ofpassing the crest facing away from the passage through the slit whileinserting a tuck of iris tissue into the slit is shown in more detail,the needle being of an instrument according to a second exemplaryembodiment of the invention.

For passing the crest 116 of the needle 108 through the slit 102, thecrest 116 is first positioned centrally behind the slit 102. Then, theclamping arms 103 are urged towards the iris 6 causing the tip ends ofthe arms 103 to be urged apart from positions 103A via positions 103B toa position 103C. In the positions 103C the tip ends of the clamping armshave been urged past the widest portion of the needle 8 and resilientlymove towards each other again due to the elastic compression of the armstowards each other, until the situation shown in FIG. 5 is reached inwhich the clamping arms 103D clamp a tuck of the iris material 1. Theclamping arms 103D in front of the passage 112 locally urge the irissurface 5 away from the rim 114 of the passage causing the adherence ofiris material 1 to the passage 112 to break up.

Seen in cross-section perpendicular to the longitudinal direction of thetip section 113, the crest 116 has a substantially smaller radius ofcurvature than neighbouring portions of the needle 108. This featurefacilitates entry of the crest 116 and subsequent portions of the needleinto the slit, because of the essentially wedge-shaped cross-section ofthe portion of the needle 108, which is leading as the needle 108 ispassed through the slit 102.

More specifically, at least in the section including the crest 116, theneedle 8 has a generally triangular cross-section perpendicular to thelongitudinal direction of that section of the needle 108. This providesthe additional advantage, that essentially the maximum width of theneedle is available for the passage 112 having a rim 114 in a flat planeto allow sealing contact with the iris surface 5 before the suction isapplied. The wider the passage 112 is, the larger the iris surfaceportion is in which the suction applied via the passage 112 is operativeand, accordingly, the more reliable the iris tissue can be made toadhere to the passage 112 in response to the applied suction.

In FIGS. 7-9, a third example of a needle for an ophthalmologic surgicalinstrument according to the invention is described. As the needle shownin FIGS. 4 and 5, this needle 208 is based on a needle having atriangular cross-section. However, similar to the needle shown in FIGS.1-3, the needle 208 according to this example has a tip section 213 thatextends at an angle from a more proximal portion 240 of the needle 208.Some alternative possibilities for the path along which the moreproximal portion of the needle extends are shown by dot and dash linesdesignated by reference numerals 240′ and 240″.

The passage 212 is manufactured by removing material from the bentdistal end portion of the tip section 213. An alternative possibility ofthe shape of the tip section is shown by dot and dash lines designatedby reference numeral 213″.

In the lumen 218 closely adjacent the passage 212, a shield 242 isprovided. This shield 242 bounds a tuck receiving chamber 243 behind theopening 212 for preventing iris tissue 1 from being aspired away fromthe passage 212 beyond the tuck receiving chamber 243, thereby reducingthe risk of damage to the tissue. In this example, the shield 242 isprovided in the form of a lip of wall material of the needle 208, whichis bent into the lumen 218. However, it is also possible to provide theshield in others forms, such as in the form of a plug or grate whichallows fluid to pass, but restrains iris tissue from being displacedbeyond the shield.

In FIGS. 10 and 11 a fourth example of a needle for an instrumentaccording to the invention is described in which the crest 316 is notlocated diametrically opposite of the passage. In this example, theneedle 308 is of a twin barrel type and has two lumen 318 communicatingwith two passages 312. The crest 316 is part of a bar 344interconnecting the two barrels 345 of the needle 308 and extendsbetween the barrels 345. In operation, the tuck of iris material isformed and inserted as the iris tissue adheres to the passages 312 andthe clamping arms 303 of the implant are moved towards the iris 6 andopened while the crest 316 and the bar 344 pass through the slit betweenthe arms 303 (see FIG. 9).

FIG. 12 illustrates an example of an instrument according to theinvention, which is adapted for injecting a liquid in the area where thetuck is to be formed prior to formation generating suction via thepassages. According to this example, the needle 408 is connected to thevacuum source, which in this example is formed by a pump 446. In theconduit 418 between the pump 446 and the needle, a liquid reservoir 447in incorporated. The pumping action of the pump 446 is reversible andcan be adapted to inject a predetermined volume of liquid from thereservoir 447. The liquid reservoir can also form a chamber of thevacuum source, for instance as in the syringe shown in FIGS. 1-3 so thatthe need of a separate component is avoided. Provision of a separate,pre-filled reservoir cartridge can however, be advantageous tofacilitate handling while ensuring sterile conditions. The liquid ispreferably conventional saline and serves for displacing visco-elasticliquid such as HPMC (HydroxyPropylMethylCellulose) or Sodiumhyaluron inthe area of the tuck to be formed to improve adherence of the iristissue to the passage via which suction is applied and to reduce leakagebetween the rim of the passage and the surface of iris tissue.

The saline or another liquid introduced into the eye can also beadvantageous for preventing under pressure which causes the cornea tobuckle which in turn distorts the surgeon's vision into the anteriorchamber of the eye. Liquid can be injected gradually during theapplication of suction, as a compensation for liquid withdrawn from theeye in the course of applying suction for adhering the needle to theiris surface. Alternatively, or in addition, a buffer dose of liquid canbe injected into the eye for causing a temporary excess pressure andallowing the removal of some of the visco-elastic liquid beforesignificant buckling of the cornea occurs.

Since the liquid reservoir 447 communicates with the passage in theneedle 408 via which suction is applied to the iris tissue, a separatelumen or a separate insertion of an instrument for transporting theliquid to the eye is not necessary. However, it is also possible toprovide a lumen for feeding liquid to the eye separate from the lumencommunicating with the passage for providing a vacuum at the passage.

In FIG. 13 an example of an instrument according to the invention isshown in which the means for applying suction at the passage adjacentthe tip of the needle 508 are formed by a conduit 518 which can beconnected to a vacuum source. In use, the conduit 518 is preferablyconnected to a vacuum source, which is adjustable for varying the flowrate, the vacuum or both. For instance phako-emulsification apparatustypically includes a vacuum pump capable of providing a continuous(partial) vacuum. Thus, use can be made of a vacuum, which is typicallypresent in an ophthalmologic surgery.

For controlling suction at the passage, a venting passage 548communicating with the conduit 518 is provided, which can be closedselectively with the tip of a finger. The elongate grip 549 in which theventing passage 548 is provided is rotatable about it longitudinal axisrelative to the needle 508 to allow the venting passage 548 to belocated and oriented relative to the needle 508 in accordance with thesurgeon's preferences and ergonomics, for instance to a position 548′indicated by dash and dot lines. To this end, the instrument includes aneedle holder 550, which is rotatable relative to the grip 549 with suchfriction that the selected orientation of the needle 508 relative to thegrip 549 is retained in use. The venting passage can also be provided ina more proximal position 548″ also indicated by dash and dot lines, tobe operated with the ring finger or the little finger.

A venting opening can also be applied advantageously in a device inwhich the vacuum is not permanent, such as the instrument shown in FIG.13. In such instruments, the vent communicating with the conduit can forinstance first be held in closed-off condition, the closure beingreleased after insertion of the tuck of iris tissue.

In FIGS. 14 and 15, a portion of the grip 549 in the area of the ventingpassage 548 is shown in more detail. In an area around the ventingpassage 548, the grip is flattened by forming a shallow trough 559transversal to the axis of the grip. This allows the precise position ofthe surgeon's finger to be less critical for adequately closing off thepassage 548.

In FIGS. 16 and 17, the venting passage 548′″ is elongate whichfacilitates dosage of the venting and thereby of the applied vacuum. Tofacilitate dosage when a very small venting flow is desired, the passage548′″ has a wide end and a narrow end. When venting via the narrow end,a given displacement of the finger partially closing off the ventingpassage in longitudinal direction of the passage's cross-section resultsin smaller variation in the venting flow than when venting via the wideend.

FIGS. 18-20 show a fifth example of a needle 608 for use in aninstrument according to the invention. Also this needle 608 is adaptedfor exerting forces on the implant for urging at least one of the endportions of the clamping arms 603 towards the iris. According to thisexample, the needle 608 includes a sheath 651, which is axially andreciprocally movable over a core 652 of the needle 608 between aretracted position (shown in full lines) and a forward position (shownin dash and dot lines). The tip of the sheath includes a wedge 653having a front edge extending radially relative to the core 652. Fromthe front edge of the wedge, guide surfaces 654 forming the front end ofthe sheath 651 extend along opposite sides of the core 652 in proximaldirection and about half the circumference of the core 652 and meet atthe side of the core 652 facing away from the wedge 653. At the tip endof the core 652 a retainer 655 is arranged, which retainer includes aslot 656 dimensioned to receive a tip end of the wedge 653.

In use, the core 652 is positioned between the iris surface and the tipends of the arms 603A of the implant 604 while the sheath 651 is in itsretracted position. Next, the sheath 651 is urged to its forwardposition causing the guide surfaces to engage the tips of the arms 603.The retainer 655 prevents the tips of the arras from moving axially indistal direction in response to the forces exerted thereon by the guidesurfaces 654. Thus, the guide surfaces 654 and the retainer 655co-operate to urge the tips of the clamping arms 603 towards theposition indicated with reference number 603B. In the meantime, iristissue adheres to the passage 612 near the tip end of the needle and atuck of the iris tissue is pinched between the ends of the arms 603reaching a position between the core 652 of the needle 608 and the restof the iris.

Since the distal end portion of the ophthalmologic surgical instrumentexerts at least a portion of the forces towards the iris by engaging atleast one of the end portions of the clamping arms 603, the forces areintroduced near the position where the displacement is required, so thatrelatively small forces suffice for effecting the required displacementagainst elastic forces exerted by the material of the implant 604 and avery direct control of the displacements is obtained.

Moreover, the needle 608 of the ophthalmologic instrument according tothis example is inserted via an incision 657 and is brought in aposition extending from that incision 657 in a direction of a centralportion of the implant 604 and curving away from the central portiontowards at least one of the end portions of the clamping arms 603. Thisprovides the advantage that both tucks at opposite ends of the implant604 can be inserted operating via the same incision. A separate incisionsuch as depicted at 658 in line with a longitudinal cross-section of theimplant is therefore not required.

Although in the previous examples, the distal end portion is describedas being formed by a needle, other generally elongate tubular forms ofthe distal end portion are conceivable as well, such as a flat strip ora flexible tube combined with an arm carrying the crest to be urged intothe slit and the passage bounded by a rim to which the iris tissue to beinserted into the slit is to adhere. It is also noted that, inprinciple, each of the examples of the needles can be combined with eachof the examples of the grips and means for applying and controlling thevacuum.

1. An ophthalmologic surgical instrument for inserting a tuck of iristissue in a pinching area between clamping arms of an intraocularimplant to be attached to a surface of the iris in an anterior chamberof an eye, comprising: an elongate distal end portion for insertion intothe anterior chamber, said distal end portion comprising a laterallyfacing entry passage in an elongate distal tip section of the distal endportion, said distal tip section generally extending in an axialdirection, said passage having an entry area bounded by a rim extendingin a single plane for sealingly contacting the iris tissue surface, andan external crest facing away from and extending essentially parallel tosaid plane, for urging open the pinching area between the clamping arms;and a conduit extending from said passage for transferring a vacuum tosaid passage from at least a more proximal portion of the instrument;wherein, in cross-sectional view of the distal tip section perpendicularto the axial direction, the crest has a substantially smaller radius ofcurvature than neighboring wall portions of the distal end portion. 2.An instrument according to claim 1, wherein in cross-sectional view ofthe distal tip section perpendicular to the axial direction, the distaltip section has a generally triangular outermost contour.
 3. Anophthalmologic surgical instrument for inserting a tuck of iris tissuein a pinching area between clamping arms of an intraocular implant to beattached to a surface of the iris in an anterior chamber of an eye,comprising: an elongate distal end portion for insertion into theanterior chamber, said distal end portion generally extending in anaxial direction and comprising a laterally facing entry passage in adistal tip section of the distal end portion, said passage having anentry area bounded by a rim extending in a single plane for sealinglycontacting the iris tissue surface and a crest facing away from andextending essentially parallel to said plane, for urging open thepinching area between the clamping arms; and a lumen extending from saidpassage for transferring a vacuum to said passage from at least a moreproximal portion of the instrument; and a shield in said lumen closelyadjacent said passage, said shield bounding a tuck receiving chamberbehind the passage and extending transversely to said lumen proximallyof said passage, for preventing iris tissue from being aspired away fromsaid passage beyond said tuck receiving chamber.
 4. An ophthalmologicsurgical instrument for inserting a tuck of iris tissue in a pinchingarea between clamping arms of an intraocular implant to be attached to asurface of the iris in an anterior chamber of an eye, comprising: anelongate distal end portion for insertion into the anterior chamber,said distal end portion generally extending in an axial direction andcomprising a laterally facing entry passage in a distal tip section ofthe distal end portion, said passage having an entry area bounded by arim extending in a single plane for sealingly contacting the iris tissuesurface, and an external crest facing away from and extendingessentially parallel to said plane, for urging open the pinching areabetween the clamping arms; and a conduit extending from said passage fortransferring a vacuum to said passage from at least a more proximalportion of the instrument, wherein said conduit and said distal endportion for insertion into the anterior chamber are free from cuttingtools.
 5. An instrument according to claim 4, wherein the distal tipsection of the distal end portion extends at an angle to a next sectionof the distal end portion proximal of said tip section.
 6. An instrumentaccording to claim 4, wherein said rim extends in a plane essentiallyparallel to at least a tip section of said distal end portion.
 7. Aninstrument according to claim 4, wherein said passage has an elongateshape.
 8. An instrument according to claim 4, wherein said distal endportion is transparent in at least an area opposite said passage.
 9. Aninstrument according to claim 4, wherein the tip end of the distal endportion is closed.
 10. An instrument according to claim 4, wherein, atleast in the section including said crest, said distal end portion has awidth measured parallel to the rim of said passage, of less than 1 mm.